This invention relates to recording apparatus, and particularly to a recording apparatus suitable for use in recording as a visible image such an electric picture information signal as is presented on facsimile, computer terminal or the like.
The recording apparatus in facsimile and the printer of computer terminal, which record an electrical picture information signal as a visible image, employ the thermal printing method, or electrostatic printing method.
In the thermal printing method, thermal printing paper which colors when heated is used and the thermal printing head is made in contact therewith to record an information picture thereon by driving the head in accordance with an electric picture information signal. This method provides a relatively simple recording mechanism, but the printing paper to be used in this method is set to a coloring temperature as high as 60.degree. to 70.degree. C. in order to prevent coloring at the normal temperature. Therefore, the thermal printing head, once driven, will not easily be reduced to a low temperature due to its thermal inertia and thus it is difficult to record at high speed. Also, since the reaction coloring agent of printing paper secularly changes, it is difficult to keep the recorded picture image in good condition for a long time.
The electrostatic printing method includes the multistylus recording method in which electrostatic printing paper is used, and a multistylus printing head is driven by an electric picture information signal to record on the electrostatic printing paper an electrostatic latent image which is then developed with toner, and a laser beam recording method using electronic photograph technique. In the multistylus recording method, the printing head is driven in accordance with an electric picture information signal to record an electrostatic latent image on the electrostatic printing paper by the corona discharge from the multistylus. Therefore, the drive circuit for the printing head needs a switching element of high breakdown voltage and the discharge characteristic of multistylus is affected by the moisture of the atmosphere to change the darkness of recorded image. On the other hand, in the laser beam recording method, a medium of a photoconductive, photosensitive material is used, and the laser beam modulated in its intensity by an electric picture information signal is emitted onto the surface of the medium to record an electrostatic latent image on the surface of the medium. This method, however, requires a complex control for deflecting the laser beam to scan.